“I think when you keep a secret and when you keep silent about something, you do it because you think it’s keeping you safe, but in fact, it’s deadly,” Alford told NBC’s Meredith Vieira in an exclusive interview to air Wednesday on Rock Center with Brian Williams.

The 19-year-old spent the summer of 1962 in the White House press office after completing her freshman year at Wheaton College in Massachusetts. Just four days into her internship, JFK aide David Powers approached her and invited her to go swimming in the White House pool. A 45-year-old Kennedy was quick to keep her company, along with two others, in the pool.

“It really didn’t seem unnatural, just because everybody was friendly and I went back to work afterward,” Alford said. “No one said anything.”

The president called her later that day to ask if she would like to tour the private floors of the White House. Naivety prevailing, Alford agreed.

“The president came over to me and asked me if I’d like to take a tour of the second floor of the White House and see some of the rooms that had been redecorated. The last room that we went into was the bedroom and we walked into the bedroom and it was a beautiful room ... I learned later that it was Mrs. Kennedy’s bedroom,” Alford said.

Alford alleges that she lost her virginity to Kennedy in the first lady’s bed.

“I wouldn’t describe what happened that night as making love, but I wouldn’t call it nonconsensual either.”

Alford went on to tell Vieira that she felt overpowered by Kennedy’s presidential aura.

“He was this unbelievably handsome man, 45 years old ... [I felt] overpowered in the fact that he had chosen me ... and taken me on this tour. That’s what I mean by being overpowered by the whole situation. Not overpowered physically that someone had grabbed me and done this to me and made me do something that I wasn’t really willing to do, because I really think I was willing to do it.”

The affair lasted for 18 months, even after Alford’s internship ended and she returned to college.

Looking back, she says she should have felt guilty, but Kennedy made her feel special.

“I’m not going to say he loved me, but I think he did like me a lot. He cared about me,” she reflected. “Just the way he was, the way he smiled with me. I feel that he did. I feel that he actually cared about me.”